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Modellstudie av föroreningsretention i Bäckaslövs våtmark : Tillämpning av modellverktygen MIKE SHE WET och MIKE 21Bosson, Emma January 2004 (has links)
<p>During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland. Simulations in two different modelling programs, MIKE SHE WET and MIKE 21 have been performed. MIKE SHE WET has never been used in practical work. The purpose of the program is to describe chemical and biological processes in wetlands and how the plants affect the retention of nutrients in the water. Since the program never has been used before, the main work has been to test the model to investigate whether it fulfil its purpose or not. MIKE 21 has been used to describe how the geometry influences the retention of suspended material, nitrogen and phosphorus. MIKE 21 has also been used to study how the wetland works without the storm water pond. To be able to describe the natural processes going on in wetlands the program MIKE SHE WET has to be further developed. The work has yet resulted in a package of measures that can improve the model. Science is in need for a model like MIKE SHE WET. If the program will be edited it can contribute a lot to the research of wetlands and storm water treatment. The simulations in MIKE 21 show that today’s shape of the wetland is not most favourable. If the water was spread over a bigger area the retention of nitrogen, phosphorus and suspended material would increase.</p> / <p>Anläggandet av konstgjorda våtmarker och sedimenteringsdammar har varit intensivt under nittiotalet och ekologisk dagvattenhantering har blivit mycket populärt i Sveriges kommuner. DHI Water and Environment bedriver i samarbete med Chalmers tekniska Högskola samt Växjö och Örebro kommuner ett forskningsprojekt kring anlagda dammar och våtmarker. Meningen är att resultaten ska kunna användas vid såväl uppföljningsarbete av befintliga dammar samt vid anläggandet av nya dagvattenanläggningar. Detta examensarbete ingår som en del av ovan nämnda forskningsprojekt. Arbetet har tillämpats på Bäckaslövs dagvattenanläggning i Växjö. Anläggningen består av en sedimenteringsdamm med efterföljande våtmark. Modellstudier har utförts i två olika modellprogram, MIKE SHE WET och MIKE 21. MIKE SHE WET har inte tidigare använts i praktiken och har därför testats för att undersöka om programmet uppfyller sitt syfte. Programmet har utformats för att kunna simulera växternas påverkan på kväve- och fosforretentionen. Med hjälp av MIKE 21 har simuleringar utförts för att undersöka hur våtmarkens geometri kan förändras för att få en optimerad avskiljning av kväve, fosfor och suspenderat material. Simuleringar har också utförts för att undersöka hur våtmarken skulle fungera utan uppströms liggande sedimenteringsdamm. Resultaten visar på att MIKE SHE WET måste vidareutvecklas för att kunna beskriva de biologiska och kemiska processer som pågår i våtmarken. Arbetet har lett fram till ett antal konkreta åtgärdsförslag för att förbättra programmet och modellen har potential att bli ett viktigt hjälpmedel i framtida forskning kring våtmarker. MIKE 21-simuleringarna har visat mycket goda resultat. Resultaten visar på att våtmarken idag inte har optimal utformning för att kunna rena det dagvatten som flödar in i den. Om våtmarken utformas så att vattnet får en större spridning i området kommer reningen av såväl suspenderat material som kväve och fosfor att förbättras.</p>
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Hydrologie et modélisation hydrologique des tourbières acides du Massif Central (France) / Hydrology and hydrological modelling of acidic mires in central FranceDuranel, Arnaud 23 March 2016 (has links)
L'objet de la présente thèse est de caractériser, quantifier et modéliser les flux d'eau au sein de la Réserve Naturelle Nationale de la Tourbière des Dauges, située en Limousin (Massif Central, France) et qui inclue une tourbière acide de fond de vallon et son bassin versant. Un ensemble de techniques, incluant la description de coupes superficielles existantes, la réinterprétation de sondages géologiques profonds, la tomographie de résistivité électrique et une modélisation de la distribution spatiale des formations affleurantes, ont été utilisées pour caractériser la nature et la géométrie des formations d'altération du granite. Les dépôts alluviaux et tourbeux ont été caractérisés et cartographiés par sondage à la tarière et à la tige filetée, et leur conductivité hydraulique estimée par choc hydraulique. Les précipitations, les paramètres météorologiques nécessaires au calcul de l'évapotranspiration potentielle, les débits et niveaux dans les ruisseaux, et les niveaux piézométriques dans la tourbe et les formations minérales sous jacentes ont été mesurés en continu pendant trois ans. Le modèle hydrologique distribué à base physique MIKE SHE / MIKE 11 a été utilisé pour modéliser les écoulements et les niveaux piézométriques au sein de la tourbière et de son bassin versant avec un pas de temps quotidien et une résolution spatiale de IO m. Il est montré que les apports souterrains issus de la zone fissurée du granite et suintant au travers du dépôt tourbeux constituent une part quantitativement importante et fonctionnellement essentielle de la balance hydrique de la zone humide. La présence d'une nappe affleurante entraîne une évacuation rapide vers les cours d'eau des apports par ruissellement ou par précipitation directe du fait de la saturation des histosols. Toutefois, il est montré que le fonctionnement hydrologique à l'échelle locale peut s'éloigner de ce schéma général du fait d'une grande hétérogénéité du taux d'humification et de la conductivité hydraulique de la tourbe, de la présence de dépôts alluviaux très perméables sous ou au sein du dépôt tourbeux et de perturbations anthropiques passées. Une fois calibré, le modèle hydrologique, qui représente la zone fissurée du socle granitique comme un milieu poreux équivalent, donne des résultats satisfaisants à très bons selon les indicateurs de performance utilisés: il est capable de reproduire les débits dans les cours d'eau au niveau des quatre stations de jaugeage disponibles, et le niveau de la nappe dans la plupart des piézomètres installés. A l'échelle du bassin versant étudié, le niveau moyen de la nappe simulé par le modèle montre une très bonne concordance avec la distribution observée des végétations de zone humide, cartographiée de manière indépendante. Les analyses de sensibilité ont montré que la porosité efficace et la conductivité hydraulique horizontale de la zone fissurée du granite sont les paramètres auxquels les débits et les niveaux de nappe (y compris dans la tourbe) simulés par le modèle sont les plus sensibles, ce qui démontre l'importance d'une meilleure caractérisation des formations d'altération du granite dans tout le bassin versant pour la compréhension et la modélisation du fonctionnement hydrologique de ce type de zone humide. Le modèle a été utilisé pour simuler l'impact potentiel d'un changement d'occupation des sols au sein du bassin versant sur la balance hydrique et les niveaux de nappe dans la zone humide, ainsi que sur les débits dans les cours d'eau. Le modèle suggère que le remplacement des végétations conduirait à une réduction substantielle des apports de surface et souterrains à la tourbière et à un abaissement conséquent des niveaux de nappe dans les histosols en période estivale. / This thesis identifies, quantifies and models water fluxes within the Dauges National Nature Reserve, an acidic valley mire in the French Massif Central. A range of techniques were used to investigate the nature and geometry of granite weathering formations and of peat deposits. Rainfall, reference evapotranspiration, stream discharge, stream stage, groundwater table depths and piezometric heads were monitored over a three-year period. The distributed, physics-based hydrological model MIKE SHE / MIKE 11 was used to model water flow within the mire and its catchment. lt was shown that the mire is mostly fed by groundwater flowing within the densely fissured granite zone and upwelling through the peat deposits. Upwelling to the peat layer and see page to overland flow were highest along the mire boundaries. However hydrological functioning differs from this general conceptual model in some locations due to the high variability of the peat hydraulic characteristics, the presence of highly permeable alluvial deposits of past human interference including drainage. The equivalent porous medium approach used to mode groundwater flow within the fissured granite zone gave satisfactory results : the model was able to reproduce discharge at several locations within the high-relief catchment and groundwater table depth in most monitoring points. Sensitivity analyses showed that the specific yield and horizontal hydraulic conductivity of the fissured zone are the parameter to which simulated stream discharge and groundwater table depth, including in peat, are most sensitive. The model was forced with new vegetation pararneters to assess the potential impacts of changes in catchment land use on the mire hydrological conditions. Replacement of the broad leaf woodlands that currently cover most of the catchment with conifer plantations would lead to a substantial reduction in surface and groundwater intlows to the mire and to a substantial drop in summer groundwater table depths, particularly along the mire margins.
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Modellstudie av föroreningsretention i Bäckaslövs våtmark : Tillämpning av modellverktygen MIKE SHE WET och MIKE 21Bosson, Emma January 2004 (has links)
During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland. Simulations in two different modelling programs, MIKE SHE WET and MIKE 21 have been performed. MIKE SHE WET has never been used in practical work. The purpose of the program is to describe chemical and biological processes in wetlands and how the plants affect the retention of nutrients in the water. Since the program never has been used before, the main work has been to test the model to investigate whether it fulfil its purpose or not. MIKE 21 has been used to describe how the geometry influences the retention of suspended material, nitrogen and phosphorus. MIKE 21 has also been used to study how the wetland works without the storm water pond. To be able to describe the natural processes going on in wetlands the program MIKE SHE WET has to be further developed. The work has yet resulted in a package of measures that can improve the model. Science is in need for a model like MIKE SHE WET. If the program will be edited it can contribute a lot to the research of wetlands and storm water treatment. The simulations in MIKE 21 show that today’s shape of the wetland is not most favourable. If the water was spread over a bigger area the retention of nitrogen, phosphorus and suspended material would increase. / Anläggandet av konstgjorda våtmarker och sedimenteringsdammar har varit intensivt under nittiotalet och ekologisk dagvattenhantering har blivit mycket populärt i Sveriges kommuner. DHI Water and Environment bedriver i samarbete med Chalmers tekniska Högskola samt Växjö och Örebro kommuner ett forskningsprojekt kring anlagda dammar och våtmarker. Meningen är att resultaten ska kunna användas vid såväl uppföljningsarbete av befintliga dammar samt vid anläggandet av nya dagvattenanläggningar. Detta examensarbete ingår som en del av ovan nämnda forskningsprojekt. Arbetet har tillämpats på Bäckaslövs dagvattenanläggning i Växjö. Anläggningen består av en sedimenteringsdamm med efterföljande våtmark. Modellstudier har utförts i två olika modellprogram, MIKE SHE WET och MIKE 21. MIKE SHE WET har inte tidigare använts i praktiken och har därför testats för att undersöka om programmet uppfyller sitt syfte. Programmet har utformats för att kunna simulera växternas påverkan på kväve- och fosforretentionen. Med hjälp av MIKE 21 har simuleringar utförts för att undersöka hur våtmarkens geometri kan förändras för att få en optimerad avskiljning av kväve, fosfor och suspenderat material. Simuleringar har också utförts för att undersöka hur våtmarken skulle fungera utan uppströms liggande sedimenteringsdamm. Resultaten visar på att MIKE SHE WET måste vidareutvecklas för att kunna beskriva de biologiska och kemiska processer som pågår i våtmarken. Arbetet har lett fram till ett antal konkreta åtgärdsförslag för att förbättra programmet och modellen har potential att bli ett viktigt hjälpmedel i framtida forskning kring våtmarker. MIKE 21-simuleringarna har visat mycket goda resultat. Resultaten visar på att våtmarken idag inte har optimal utformning för att kunna rena det dagvatten som flödar in i den. Om våtmarken utformas så att vattnet får en större spridning i området kommer reningen av såväl suspenderat material som kväve och fosfor att förbättras.
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Evaluating the Potential for Low Impact Development to Mitigate Impacts of Urbanization on Groundwater Dependent Ecosystems using MIKE SHEDekker, Peter Andrew 11 January 2013 (has links)
Groundwater dependent ecosystems (GDEs), including wetlands and river baseflow systems, are a topic of substantial scientific study. The degradation of GDEs due to urbanization has been well documented. An altered hydrologic regime, through increased impervious area resulting in a flashier hydrologic regime with lower troughs, higher peaks, and quicker changes, has been recognized as a main factor affecting ecological condition. Yet studies on GDEs rarely include a hydrologic modelling component.
In this study, the conjunctive hydrologic model MIKE SHE was used to simulate the Lovers Creek subwatershed near Barrie, ON. The hydrologic regime was simulated for pre-development (natural), current (urbanized), and various low-impact development (LID) land use scenarios. The results were linked to the ecological condition via the TQmean metric, which has been used in the literature to relate the hydrologic and ecological conditions of streams.
The highest percentage LID scenario restored, on average, 11% of the reduction in TQmean that occurred from pre-development to urbanized conditions, indicating that LID has the potential to protect GDEs in urbanized watersheds. It is expected that the effect of LID would be amplified if considered on a more local scale within a predominantly high density urban area. Recommendations for future modelling efforts to evaluate GDEs and represent LID are made.
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An Integrated Flow and Transport Model to Study the Impact of Mercury Remediation Strategies for East Fork Poplar Creek Watershed, Oak Ridge, TennesseeLong, Stephanie 26 October 2009 (has links)
An integrated flow and transport model using MIKE SHE/MIKE 11 software was developed to predict the flow and transport of mercury, Hg(II), under varying environmental conditions. The model analyzed the impact of remediation scenarios within the East Fork Poplar Creek watershed of the Oak Ridge Reservation with respect to downstream concentration of mercury. The numerical simulations included the entire hydrological cycle: flow in rivers, overland flow, groundwater flow in the saturated and unsaturated zones, and evapotranspiration and precipitation time series. Stochastic parameters and hydrologic conditions over a five year period of historical hydrological data were used to analyze the hydrological cycle and to determine the prevailing mercury transport mechanism within the watershed. Simulations of remediation scenarios revealed that reduction of the highly contaminated point sources, rather than general remediation of the contaminant plume, has a more direct impact on downstream mercury concentrations.
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Artificial groundwater recharge in wetlands: pre modelling for a pilot study in Forsmark, Sweden.Bergström, Maria January 2013 (has links)
The Swedish Nuclear Fuel and Waste Management Company, SKB, is planning to construct a deep geological repository for spent nuclear fuel in Forsmark, Sweden. Leakage of groundwater into the repository during the construction and operational phases might cause a groundwater drawdown that in turn may affect the hydrological conditions in sensitive habitats in the area. The sensitive habitats in question are wetlands, home to several protected species. SKB has planned to take mitigation measures in the case variations of the surface-water elevation are identified for the concerned wetlands. The mitigations measures consists in infiltrating water in the ground in the direct vicinity to the wetland to create a higher groundwater pressure that then will propagate to the surface-water. This study describes the modelling of a pilot-study of such a measure and aims at serving as one of the background materials for the planning and design of the pilot study. The aims of the pilot study are to show that the surface-water level in a wetland can be controlled and to gain knowledge and experiences regarding artificial groundwater recharge for this purpose. The pilot study would take place before the construction of the repository so the undisturbed case is considered. The results show that an infiltration facility can control the surface-water level in a wetland. It is also shown that an infiltration rate of 0.5 L/s is enough to manipulate the surface-water level in the undisturbed condition.
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Modelling the effects of land use change on a peri-urban catchment in Portugal / Modellering av hur förändrad markanvändning påverkar ett avrinningsområde i PortugalHävermark, Saga January 2016 (has links)
Societal developments are associated with land use change, and with urbanization in particular. Urbanization can influence hydrological processes by decreasing evapotranspiration and infiltration as well as by increasing streamflow, peak flow and overland flow. This causes higher risks of flooding. Although several studies have investigated the impacts of urbanization on streamflow over the last decades, less is known about how urbanization affects the hydrological processes in peri-urban areas characterized by a complex mosaic of different land uses. This study aimed to model the impact of land use change, or more specifically urbanization, on the hydrological responses of the small peri-urban Ribeira dos Covões catchment (6.2 km2) located in central Portugal. The catchment has undergone rapid land use change since the mid- 1950s associated with conversion of agricultural fields (decreased from 48 to 4%) into woodland and urban areas, which increased from 44 to 56% and from 8 to 40%, respectively. For the study, the hydrological modelling system MIKE SHE was used. Parameters and data of climate, vegetation and soil types were used as input. There were also land use maps and daily streamflow values available for the hydrological years 2008/09 to 2012/13, which were used to calibrate and validate the model. The statistics from the calibration and validation both indicated that the model simulated the streamflow well. The model was designed to examine both how past land use change might have affected the streamflow, and to investigate the impacts on hydrology if the urban area was to be increased to cover 50% of the catchment. It was not only the importance of the urban cover’s size that was tested, but also the placement of additional urban areas. Three future scenarios were run, all with a 50% urban cover, but distributed differently within the catchment. The study did not indicate that an increase in urbanization leads to higher peak flow or streamflow. Neither could any decrease in infiltration be seen. All three scenarios however gave an increase in overland flow of approximately 10% and a decrease in evapotranspiration by 55%, regardless of where the urban areas were added. The reliability of the models can be enhanced by additional climate, soil and vegetation data. This would improve the results and make them more useful in decision making processes in the planning and management of new urban areas. / Samhällets ständiga utveckling medför förändringar i markanvändning. Utvecklingen och förändringarna är framför allt associerade med urbanisering som kan påverka ett avrinningsområdes hydrologiska processer genom att exempelvis reducera dess evapotranspiration och infiltration samt öka vattenföringen, högsta flödet och ytavrinningen. Det i sin tur ökar risken för översvämning. Trots att många studier har undersökt urbaniseringens inverkan på vattenföring de senaste decennierna saknas viss kunskap om dess påverkan på hydrologin i stadsnära avrinningsområden, kännetecknade av flera olika typer av markanvändning. Denna studie syftade till att modellera hur förändringar i markanvändning, eller mer specifikt urbanisering, påverkar hydrologin i det lilla stadsnära avrinningsområdet Ribeira dos Covões (6,2 km2) i centrala Portugal. Avrinningsområdet har genomgått snabba markanvändningsförändringar sedan mitten av 1950-talet i samband med en omvandling av åkrar (täckningsarean har minskat från 48 till 4 %) till skogsmark och urbaniserade områden, vilkas storlek har ökat från 44 till 56 % respektive 8 till 40 %. För att uppfylla syftet har den hydrologiska modellen MIKE SHE använts. Parametrar avseende klimat samt vegetations- och jordegenskaper användes som indata till modellen. Det fanns också tillgång till en markanvändningskarta över området samt dagliga flödesvärden mellan de hydrologiska åren 2008 och 2013. Dessa användes för att kalibrera och validera modellen. Statistiken för både kalibreringen och valideringen indikerade en fullt acceptabel modell. Modellen var avsedd att undersöka dels hur tidigare förändring i markanvändning kan ha påverkat vattenföringen, dels för att studera effekten på hydrologin om urbaniseringen fortgår tills dess täckning är 50 % av avrinningsområdet. Det var inte bara betydelsen av de urbana ytornas storlek som testades, utan även placeringen av dem. Tre framtidsscenarier togs fram, alla med en urban yta på 50 % fördelad olika inom avrinningsområdet. Studien indikerade inte att ytterligare urbanisering ökar vare sig flödet eller det högsta flödet. Inte heller gav de någon minskning av infiltration. Alla tre scenarierna gav emellertid en ökning av ytavrinningen med cirka 10 % och en minskning av evapotranspirationen med 55 %, oavsett placering av de urbana ytorna. Modellernas tillförlitlighet skulle kunna förbättras med hjälp av ytterligare klimat-, vegetations- och jordindata. Det skulle förbättra resultaten och göra dem användbara i beslutsfattanden vid planering och utveckling av nya urbana områden.
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Modélisation hydrologique déterministe pour les systèmes d'aide à la décision en temps réel : application au bassin versant Var, France / Deterministic hydrological modelling for real time decision support systems : application to the Var catchment, FranceMa, Qiang 14 March 2018 (has links)
Les ressources en eau sont généralement considérées comme l'une des ressources naturelles les plus importantes du développement social, en particulier pour soutenir les usages domestiques, agricoles et industriels. Au cours de la dernière décennie, en raison de l'augmentation des activités humaines, telles que l'urbanisation et l'industrialisation, les impacts sociaux sur l'environnement naturel deviennent de plus en plus intenses. Par conséquent, de nos jours, les problèmes d'eau par rapport à avant deviennent plus compliqués. Pour faire face au problème complexe depuis les années 1970, les gens ont reconnu que le système d'aide à la décision (DSS) présente des avantages évidents. De plus, avec le développement de l'informatique et des techniques web, les DSS sont souvent utilisés pour appuyer la décision locale. Les décideurs pour gérer les ressources naturelles de la région en particulier les ressources en eau. La modélisation hydrologique en charge de la représentation des caractéristiques du bassin versant joue un rôle important dans le système d'aide à la décision environnementale (EDSS). Parmi les différents types de modèles, le modèle hydrologique distribué déterministe est capable de décrire l'état réel de la zone d'étude de manière plus détaillée et précise. Cependant, le seul obstacle à la limitation des applications de ce type de modèle est pointé vers le grand besoin de données demandé par sa configuration de modélisation. Dans cette étude d'évaluation de la modélisation hydrologique dans le projet AquaVar, un modèle distribué déterministe (MIKE SHE) est construit pour l'ensemble du bassin versant du Var avec moins d'informations de terrain disponibles dans la zone. Grâce à une stratégie de modélisation raisonnable, plusieurs hypothèses sont conçues pour résoudre les problèmes de données manquantes dans les intervalles de temps quotidiens et horaires. La simulation est étalonnée sur une échelle de temps quotidienne et horaire de 2008 à 2011, qui contient un événement de crue extrême en 2011. En raison des impacts des données manquantes sur les entrées et les observations du modèle, l'évaluation de l'étalonnage de la modélisation n'est pas seulement basée sur des coefficients statistiques tels que le coefficient de Nash, mais aussi des facteurs physiques (p. ex. valeurs maximales et débit total). Le modèle calibré est capable de décrire les conditions habituelles du système hydrologique varois, et représente également le phénomène inhabituel dans le bassin versant tel que les inondations et les sécheresses. Le processus de validation mis en œuvre de 2011 à 2014 dans l'intervalle de temps journalier et horaire confirme la bonne performance de la simulation dans le Var. La simulation MIKE SHE dans Var est l'une des parties principales du système de modélisation distribuée déterministe de l'EDSS d'AquaVar. Après l'étalonnage et la validation, le modèle pourrait être utilisé pour prévoir les impacts des événements météorologiques à venir (par exemple, des crues extrêmes) dans cette région et produire les conditions aux limites pour d'autres modèles distribués déterministes dans le système. La conception de l'architecture EDSS, la stratégie de modélisation et le processus d'évaluation de modélisation présentés dans cette recherche pourraient être appliqués comme un processus de travail standard pour résoudre les problèmes similaires dans d'autres régions. / Water resource is commonly considered as one of the most important natural resources in social development especially for supporting domestic, agricultural and industrial uses. During the last decade, due to the increase of human activities, such as urbanization and industrialization, the social impacts on the natural environment become more and more intensive. Therefore, recently, water problems compared to before become more complicated. To deal with the complex problem, since 1970s, started from the companies, people recognized that the Decision Support System (DSS) has obvious advantages Moreover, with the development of computer science and web techniques, the DSS are commonly applied for supporting the local decision makers to manage the region natural resources especially the water resources. The hydrological modelling in charge of representing the catchment characteristics plays significant role in the Environment Decision Support System (EDSS). Among different kinds of models, the deterministic distributed hydrological model is able to describe the real condition of the study area in more detail and accurate way. However, the only obstacle to limit the applications of this kind of model is pointed to the large data requirement requested by its modelling set up. In this study of hydrological modelling assessment in AquaVar project, one deterministic distributed model (MIKE SHE) is built for the whole Var catchment with less field information available in the area. Through one reasonable modelling strategy, several hypothesises are conceived to solve the missing data problems within daily and hourly time intervals. The simulation is calibrated in both daily and hourly time scale from 2008 to 2011, which contains one extreme flood event at 2011. Due to the impacts of missing data on both model inputs and observations, the evaluation of modelling calibration is not only based on the statistic coefficients such as Nash coefficient, but also effected by some physical factors (e.g. peak values and total discharge). The calibrated model is able to describe usual condition of Var hydrological system, and also represent the unusual phenomenon in the catchment such as flood and drought event. The validation process implemented from 2011 to 2014 within both daily and hourly time interval further proves the good performance of the simulation in Var. The MIKE SHE simulation in Var is one of the main parts of the deterministic distributed modelling system in the EDSS of AquaVar. After the calibration and validation, the model could be able to use for forecasting the impacts of coming meteorological events (e.g. extreme flood) in this region and producing the boundary conditions for other deterministic distributed models in the system. The design of the EDSS architecture, modelling strategy and modelling evaluation process presented in this research could be applied as one standard working process for solving the similar problems in other region.
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Modellering av torkstress på vegetation i BlåGrönGråa-system i modelleringsverktyget MIKE SHE / Modeling of drought stress on vegetation in BlueGreenGray-systems in the modeling-tool MIKE SHEBacklund, Arvid January 2022 (has links)
Huvudsyftet med den här studien var att undersöka vilka parametrar som har störst inverkan på trädens vattentillgång i BlåGrönGråa-system (BGG-system), utvecklat av Edge, och vilka förbättringar som kan göras för att vegetationen bättre ska klara av torka. Ett annat mål med denna studie var attundersöka hur väl det går att efterlikna och simulera BGG-system i modelleringsverktyget MIKESHE, utvecklad av Danish Hydraulic Institute (DHI). För att undersöka vilka parametrar som har störst inverkan på BGG-systems vattenhalt varierades; storleken på tillrinningsområdet, crop factor, växtsubstrat, djup på regnbäddarna, växtval, dräneringsdjup och dräneringshastigheten. Alla simuleringarna genomfördes med meteorologisk data för perioden 1991-2020 för att underöka hur årsvariationer påverkar vattenhalten i systemet. Resultaten visar att stadsträd som inte erhåller något tillskott av vatten via tillförsel av dagvatten kommer utsättas för extremt ogynnsamma förhållanden när det kommer till vattentillgång, och att den parameter som har störst inverkan på vattenhalten i BGG-system är storleken på tillrinningsområdet. För att ytterligare förbättra vattentillgången för träden i BGG-system kan växtsubstratet förbättras genom att öka mängden växttillgängligt vatten. Detta föreslås dock framförallt för större träd eller då tillrinningsområdet inte kan utökas ytterligare. Variationen av djupet på regnbäddarna har relativt liten effekt på resultatet, vilket delvis kan förklaras av andra val i satta parametrar. Växtvalet visar sig i denna studie har liten effekt på vattenhalten, vilket delvis beror på modellens utformning och valdaparametrar. Variationen av dräneringsdjupet och dräneringshastigheten visar sig inte ha någon effekt på de resultat som undersöks i denna studie. Modellen som har satts upp beskriver systemet på ett tillförlitligt sätt, och är ett bra första steg föratt ytterligare öka förståelsen för trädens förutsättningar i dagvattenhantering. Men för att kunna dramer långtgående slutsatser om hur träden klarar av torrperioder behöver ytterligare undersökningargenomföras på BGG-system. / The main purpose of this study was to investigate which parameters have the greatest impact on thetrees’ water supply in BlueGreenGray-systems (BGG-system), developed by Edge, and what improvements can be made to the system to make the vegetation able to withstand periods of droughts better. Another aim of this study was to investigate how well it is possible to imitate and simulate BGG-systems in the modeling tool MIKE SHE, developed by the Danish Hydraulic Institute (DHI). To investigate which parameters have the greatest impact on the water content in BGG-systems the following parameters was varied; the size of the catchment area, crop factor, plant substrate, depth of the rain beds, plant selection, drainage depth and drainage rate. All simulations were performed with meteorological data for the period 1991-2020 to investigate how annual variations affect the watercontent in the system. The results show that city trees that do not receive any addition of water via the supply of stormwater will be exposed to extremely unfavorable conditions when it comes to water supply, and that the parameter that has the greatest impact on the water content in BGG-systems is the size of the catchment area. To further improve the water supply for the trees in a BGG-system, the plant substrate can be improved by increasing the amount of plant available water. However, this is mainly proposed for larger sized trees or when the catchment area cannot be expanded further. The variation in the depth of the rain beds has a relatively small effect on the result, which can be partly explained by other choices in set parameters. The choice of plant in this study has little effect on the water content, which is partly due to the model’s design and selected parameters. The variation of the drainage depth and the drainage rate does not appear to have any effect on the results examined in this study. The model that has been set up describes the system in a reliable way, and is a good first step to furtherincrease the understanding of the trees conditions in stormwater management. However, in order tobe able to draw more far-reaching conclusions about how trees cope with dry periods, further studiesneed to be carried out on BGG-systems.
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[pt] CARACTERIZAÇÃO E AVALIAÇÃO DA CONTAMINAÇÃO DAS ÁGUAS SUBTERRÂNEAS POR METAIS PESADOS DA ÁREA DE DISPOSIÇÃO DE RESÍDUOS DE RESENDE, RJ / [en] CHARACTERIZATION AND EVALUATION OF GROUNDWATER CONTAMINATION DUE TO HEAVY METALS IN A WASTE DISPOSAL AREA IN RESENDE, RJCRISTINA KEI YAMAMOTO DE OLIVEIRA 07 April 2022 (has links)
[pt] O objetivo deste trabalho é avaliar a contaminação da água subterrânea por
metais pesados provenientes da Área de Disposição de Resíduos (ADR) do
município de Resende, RJ. O escopo compreende um estudo preliminar com base
em levantamento e mapeamento de dados espaciais; investigação in situ e em
laboratório, incluindo a instalação de poços de monitoramento, amostragens e
caracterização de solos, águas subterrâneas e chorume, ensaios de condutividade
hidráulica, K; e modelagem da pluma de contaminação usando o programa MIKE
SHE. Em geral, a caracterização apresentou argilas arenosas, siltes arenosos e,
areias siltosas, cujos principais minerais foram quartzo, caulinita, e muscovita com
presença de biotita e feldspato. Os valores de K variaram de 10(-5)
a 10(-6) m/s; o pH entre 4,59 e 6,93 (água subterrânea) e 7,93 e 8,16 (chorume); a condutividade
elétrica na água variou de 0,032 a 7,113 mS/cm, coerente com os sólidos totais
dissolvidos e com maiores valores no chorume e no poço mais próximo a ADR.
Análises detectaram 14 metais dissolvidos (Al, As, B, Ba, Cd, Co, Cr, Fe, Hg, Mn,
Ni, Pb, Se e Zn) em concentrações acima do permissível por lei. A modelagem
mostrou como a distribuição espacial e a anisotropia dos solos influenciam o fluxo
e transporte do cloreto (advectivo) e do cromo (sorção). Quando são considerados
solos anisotrópicos, a pluma de Cl- atinge o Rio Paraíba do Sul, à 2,5 km de
distância, em 43 anos enquanto a pluma do Cr dista apenas 55 m da fonte. Embora
os resultados experimentais não tenham sido claros em determinar se todos os
metais encontrados são necessariamente da fonte de contaminação da ADR ou de
origens naturais, as simulações deste modelo indicaram baixo impacto ambiental
dos metais para o rio. / [en] The objective of this work is to evaluate the groundwater contamination due
to heavy metals from the Waste Disposal Area (WDA) in the municipality of
Resende, RJ. The scope consists of a preliminary assessment based on surveying
and mapping spatial data; in situ and laboratory investigation, including the
installation of monitoring wells, sampling and characterization of soils,
groundwater and waste leachate, hydraulic conductivity tests, K; and contaminant
plume modelling using the program MIKE SHE. Overall, the characterization
revealed sandy clays, sandy silts and silty sands. The predominant minerals were
quartz, kaolinite, and muscovite along with the presence of biotite and feldspar. The
values of K varied from 10(-5) to 10(-6) m/s; the pH between 4.59 and 6.93
(groundwater) and 7.93 and 8.16 (leachate); the electrical conductivity in the water
varied from 0.032 to 7.113 mS/cm, consistent with the total dissolved solids and
with higher values attributed to the leachate and the well closest to the WDA.
Analysis detected 14 dissolved metals (Al, As, B, Ba, Cd, Co, Cr, Fe, Hg, Mn, Ni,
Pb, Se and Zn) with concentrations above the legal limit. The model illustrated how
the soils spatial distribution and anisotropy influence the flow and transport of
chloride (advective) and chromium (sorption). When considering anisotropic soils,
the Clplume reached the Paraíba do Sul River, 2.5 km away, in 43 years while the
Cr plume only moved 55 m from the source. Although the experimental results were
not clear in determining whether all the metals found necessarily originated from
the contaminant source from the WDA or from natural origins, the simulations of
this model indicated a low environmental impact to the river.
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